Electromagnetic relay having an anti-chatter feature



Dec. 13, 1966 c. W.'KING ETAL 3,292,119

ELECTROMAGNETIC RELAY HAVING AN ANTI-CHATTER FEATURE Filed May 7, 1965 INVENTORS Charles W King BY Siam/8y 6. Kingmd Fig. 3 (LR The/r Affome y United States Patent M 3,292,119 ELECTROMAGNETIC RELAY HAVING AN ANTI-CHATTER FEATURE Charles W. King, Anderson, Ind., and Stanley G. Kingma,

Blacksburg, Va., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed May 7, 1965, Ser. No. 454,093 2 Claims. (Cl. 335-104) This invention relates to an electromagnetic relay and more particularly to an electromagnetic relay that is provided with means for reducing a drumming noise which which is sometimes set up when the relay actuating coil is energized from pulsating direct current.

In certain types of motor vehicle electrical systems such as that shown in the Carlson Patent 3,037,124, and in appl cation Serial No. 295,122, filed on July 15, 1963, now Patent 3,244,900, and assigned to the assignee of this invention, .a relay is used to control certain switching functions in the electrical system. This relay as shown in the above-mentioned patent and application, is connected with a junction of two diodes of a three phase full wave bridge rectifier circuit and the relay actuating coil is therefore energized with a pulsating direct current. With this type of energization, the relay at times generates a drumming noise due to the square wave characteristic of the current supplied to the relay coil.

It accordingly is one of the objects of this invention to provide a control relay which is designed to reduce its noise level of operation where the relay is fed from a pulsating current source.

Another object of this invention is to provide an electromagnetic relay where the arrnature of the relay is connected to a hinge post through a spring metal member and where the arrangement is such that a part of the armature constantly engages a part of the hinge post. It has been found that this reduces the so-called drumming noise of conventional relays where the armature does not constantly engage the hinge post and in fact is spaced from the hinge post by a spring metal hinge.

A further object of this invention is to provide an electromagnetic relay wherein the armature has an integral section which engages a hinge post during operation of the relay. In carrying this object forward, the integral section can be formed by a suitable drawing operation so that this section is drawn down a predetermined amount to engage the hinge post when the armature is secured to the hinge post by a spring hinge.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 is an end view with parts broken away of an electromagnetic relay made in accordance with this invention.

FIGURE 2 is a view on an enlarged scale of a part of the armature assembly of the relay shown in FIG- URE 1.

FIGURE 3 is a view partly in section illustrating the relationship on an enlarged scale of the armature and hinge post of the relay shown in FIGURE 1.

Referring now to the drawings and more particularly to FIGURE 1, the reference numeral designates a support such as the firewall on a motor vehicle which supports a relay 12. The relay 12 includes a metal base 14 which supports the components of the relay. These components include a metal core 18 which carries a coil winding 16 that is wound on a spool in a conventional manner. The core may be secured to the base in a manner illustrated in the patent to Rice, 2,867,702.

3,292,119 Patented Dec. 13, 1966 The base 14 of the relay supports a metal hinge post 20 which can be of the same type shown in the above-mentioned Rice patent and this hinge post can be secured to the base by peening over the core 18 at its lower end as is illustrated in the Rice patent. The upper end of the hinge post 20 is generally L-shaped as is illustrated in FIGURES 1 and 3.

The base 14 also supports a fixed contact post 22, the top end of which forms a fixed contact that cooperates with a movable contact 24 carried by a spring metal contact support 26. The contact support 26 is located below a stop 27 which forms part of an assembly 30 that is supported by the base of the relay.

The armature assembly which is designated in its entirety by reference numeral 28 includes the spring metal con tact support 26, an armature 32 formed of magnetic material and a fiat spring metal hinge part 34 which is formed of spring steel material. The spring steel contact support 26 which carries the electrical contact 24 is secured to the steel armature 32 by a rivet section 36 that is integral with the armature 32. The armature 32 has another integral extension 38 which fits within an opening 40 formed in the spring contact support 26.

The spring metal hinge 34 is provided with openings 42 and 44 which receive rivet sections 46 that are integral with the hinge post 20. These rivet sections serve to secure the spring hinge 34 to the hinge post 20 and it is seen that the spring hinge engages the top wall of the L-shaped upper end of the post 20. It is seen from FIGURE 2 that the spring hinge 34 has an opening 45. The spring hinge 34 is secured to the armature 32 by rivet sections 48 that are integral with the armature 32 and contacts a lower wall 54 of the armature 32.

The armature 32 is drawn down over an area desi nated by reference numeral 50 to provide a complementary section 52 that extends downwardly from the lower wall 54 of the armature. The section 52 fits within the opening 45 formed in the spring hinge 34 and engages the area designated by reference numeral 56 of the hinge post 20.

It will be appreciated that the spring hinge 34 normally maintains the contact 24 out of engagement with the top end of the fixed contact post 22 and also forms a resilient pivot for the armature. gized, the armature 32 is attracted toward the top end of the core 18 and the contacts 22 and 24 will close. When this relay coil is energized with pulsating direct current of the type that is provided by connecting the relay coil between two diodes of a three phase full-wave bridge rectifier network, there is a tendency for the armature to vibrate and to develop a drumming noise. It has been found that this drumming noise is reduced by the construction of this relay where the section 52 of the armature is always in engagement with section 56 of the hinge post 20. Thus, the drawn down section 52 of the armature 32 constantly engages the top end of the hinge post 20 as contrasted to relays of the type shown in the Rice patent where the spring metal hinge is located between the armature and the hinge post. In the case of the relays of this invention, the opening 45 in the spring metal hinge which receives the drawn down section 52 permits continuous engagement between the armature and the hinge post.

While the embodiments of the present invention as herein disclosed constitute a preferred form it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. An electromagnetic relay comprising, a base, a spring hinge post extending upwardly from said base having a generally L-shaped end section, said L-shaped end section having a top wall, a relay actuating coil supported by When the relay coil 16 is enersaid base, a contact post extending upwardly from said base, an armature, a fiat spring hinge having a section connected to said top wall of said L-shaped section and having another section connected to said armature, said armature having a section contacting said top wall of said L-shaped section, and a spring metal contact support connected to said armature, said contact support having a contact means which is en-gageable with the top end of said contact post when said relay coil is energized.

2. An electromagnetic relay comprising, a base, a spring hinge post extending from said base having a generally L-shaped end, a relay actuating coil supported by said base, an armature, a flat spring metal hinge connecting said armature and said hinge post, said flat metal spring hinge engaging a top wall of said L-shaped section and a lower wall of said armature, an opening in said spring metal hinge, said armature having a section projecting through said opening and engaging said top wall of said L-shaped section, and contact means controlled by movement of said armature.

References Cited by the Examiner UNITED STATES PATENTS BERNARD A. GILHEANY, Primary Examiner,

B. DOBECK, Examiner. 

1. AN ELECTROMAGNETIC RELAY COMPRISING, A BASE, A SPRING HINGE POST EXTENDING UPWARDLY FROM SAID BASE HAVING A GENERALLY L-SHAPED END SECTION, SAID L-SHAPED END SECTION HAVING A TOP WALL, A RELAY ACTUATING COIL SUPPORTED BY SAID BASE, A CONTACT POST EXTENDING UPWARDLY FROM SAID BASE, AN ARMATURE, A FLAT SPRING HINGE HAVING A SECTION CONNECTED TO SAID TOP WALL OF SAID L-SHAPED SECTION AND HAVING ANOTHER SECTION CONNECTED TO SAID ARMATURE, SAID ARMATURE HAVING A SECTION CONTACTING SAID TOP WALL OF SAID L-SHAPED SECTION, AND A SPRING METAL CONTACT SUPPORT 